Improvement in refrigerating processes and apparatus



S D. LOUNT.

REFRIGERATING PROCESS AND APPARATUS.

No.175,Z91".q,,-- Patented March 28,1876.

Fly. 2,.

N. EETERS, FHOTQ-UTHQGRAPHER, WASHINGTON, n C.

WITNESSES UNITED STATES PATENT CFFTCE.

SAMUEL D. LOUNT, OF GHATTANOOGA, TENNESSEE.

IMPROVEMENT IN REFRIGERATING PROCESSES AND APPARATUS.

Specification forming part of Letters Patent No. [75,291, dated March 28, 1876; application filed December 27, 1875.

,liquid or condensed gas in the rear of said f surfaces; and the object of my invention is,

first, to keep such surfaces free from frost or snow, caused by the freezing of the moisture which is always presentin the air to be cooled.

i This frost or snow soon covers the refrigerating-surface with a non-conducting envelope, and thus necessitates the use of alarge surface and the circulation of a large quantity of air at a comparatively high temperature, when the same work couldibe accomplished with much less refrigerating-surface, and the circulation of a much less quantity of air at as low a temperature as could be obtained by bring ing it in direct contact with the refrigeratingsurface. Second, to bring a much greater refrigerating-surface in contact with the air to be cooled than is furnished by the pipes or other metallic envelope containing the refrigerant, and also to bring all portions of the air into intimate contact with said surfaces.

Third, to free the ain tobe cpoled from moist- T the freezing-point 'of water, and cooled by contact with the outside of vessels containing a volatile refrigerant, and in the process of cooling air by bringing it into contact with any such incongealable liquid while in the condition of spray, drops, streams, or showers, such liquid being refrigerated by contact with the opposite sides of vessels containing a volatile refrigerant; and my invention further consists in an apparatus for carrying out these processes.

The above objects are all practically and economically attainable by my apparatus,

which I will now' describe.

Figure 2 is a cross-section of one arrangement of the refrigerating-pipes, &c., in position in the apartment constructed to receive them. Fig. lisa longitudinal section, showing one of the flat coils, with the compressingpump D and a circulating-pump, E.

The same letters refer to the same parts in both views.

O G is a series of or a single flat coil of pipe, similar to those used in steam=heating. The refrigerant is constantly drawn through the pipe 0 by the pump D, which can be directly connected with said pipe, or through any retorting or absorbing apparatus. The discharge-pipe of pump D returns the condensed gas or vapor to pipe 0 through the usual boilers (if boilers are employed) and condensers,

there-to be again evaporated and circulated, as before. As this process is common to all machines of this class, it is not necessary to describe it minutely; but the well-known result of the evaporation of the condensed gas or vapor in pipe 0 is, that heat is rapidly abstracted from the surrounding air, and the pipe, in thewell-known methods heretofore employed, soon receives a thick coating of frost or snow, which, as before stated, seriously interferes with the usefulness of the apparatus.

Now, to prevent this deposit, and for other r purposes, hereafter mentioned, I keep the pipe 0 constantly coated or covered with gly erine, i

or some other incongealable fluid, as is a or mentioned and described, which fluid can be delivered on the pipes G through perforations in the bottom of the tanks A A, or by any other suitable nieans-as, for instance, perforated pipes-either continuously or intermittently, and after flowing over said pipes it is received in tank or tanks 13 B, from which it can be again taken by pump E, or otherwise, and applied again to the pipes, as before.

Any fluid incongealable at or near the freezing-point of water can he used; but I prefer glycerine for the following reasons Being a viscid liquid, it will spread more thoroughly over and remain longer in contact with the freezing-s11rfaces. thereby becoming more thoroughly refrigerated. It has a strong chemical afiinity for water, thus freeing the air from vapor by the aid of such afiinity, as well as by condensation. Air passing through it will not be so liable to carry fine particles of it along by mere friction of the current. and if any particles are so conveyed to the articles which are to be refrigerated, they will not impart any objectionable taste or odor, or injure them in any way. Instead of corroding the metallic surfaces with which it comes In contact, it will preserve them from rust, and also lubricate the circulating-pump, when one is used.

The pipes or cases containing the refrigerant can be arranged and the liquid applied in various ways. Forinstance,they can be placed in tanks and entirely submerged in the incongealable liquid, and the air forced through and in contact with the liquid, or passed over and against the surface of the liquid or the liquid, after being refrigerated, can be spread over suitable surfaces in thin films, or divided into spray or drops while the air is brought into contact with it.

One of the objects of the arrangement of the apparatus shown in Figs. 1 and 2 is to di' vide the incongealable liquid into strealns or drops, and thereby bring the air into intimate contact with a large refrigerating-surface, and also to use some substance for said surface which has a chemical affinity for water, thereby bringing the vapor with which the air is charged under the influence of such affinity, when it is in the best condition to be acted upon by such aflinity-that is, when the air is at the lowest attainable temperature; and my invention embraces the use of any liquid which is incongealable, as above mentioned, when said liquid is cooled by contact with the outside surfaces of channels or cases inclosing a refrigerant, and is then brought into direct contact with the air to be cooled.

It is evident that the refrigerant may be outside and the incongealable liquid inside the inclosed surfaces.

To prevent the formation of frost only, it is not necessary that the incongealable liquid should be kept in constant circulation, forl have kept metallic surfaces below 32 Fahrenheit in contact with damp air for some hours without their being covered with frost, by simply applying a single coating or film of g'lycerine.

The glycerine or other liquid used will even tually absorb vapor from the air until it will congeal, unless the whole or a portion of it is drawn ofi' occasionally and concentrated by heat. The exhaust-steam from the engine can be utilized for this purpose.

The pipes, channels, or cases containing the volatile refrigerant, and covered or coated with incongealable liquid can be placed in the same closed apartmeiit with the articles to be refrigerated, and the temperature be reduced by radiation and natural currents of air, and this arrangement is embraced in my invention, and shown in Fig. 2 of the drawings; but if so arranged the articles to be refrigerated are liable to become contaminated with the vapor of the volatile refrigerant in case of leakage from the pipes or cases containing it.

To prevent such result I propose to place the articles to be refrigerated in an apartment or apartments, closed or not so, as desired, entirely separate from the one containing the pipes or cases above mentioned, and to connect these apartments with a suitable channel, 0, or channels for conveying the'cold air, and also a channel, It, or channels for returnin g the air, if desired, to the refrigerating'surfaces, and to provide'these channels with suitable gates or valves P P, which can be readily and entirely closed in case of the escape of the volatile refrigerant from the pipes or cases containing it. These gates or valves should be so arranged that a person in either apartment can instantly close all the connect ing air-channels.

The arrangement of a coil or coils of pipe, placed as shown in Fig. 2, in the upper part of an apartment to be refrigerated, with the tight floor or tank B /ar catching condensed moisture, and having" provisions made for a constant circulation of air between the pipes, makes an effective refrigerator without the use of the incongealableliquid, whenever it is not required to keep the lower part at a very low temperature; but a much greater length or size of pipe would be required. In .such case the chamber L is, preferably, closed to communication with other apartments or the outer air. A current of air would naturally flow down through an opening in the center of the floor or tank B B to the bottom of the lower apartment, and return up the outside and through the lines 70 k and apertures 1 I, which, as well as the'flues k 70, may be provided with valves m m, as shown; but a fan, F, should be employed whenever rapid or extensive cooling is required.

I am aware that it has been proposed to free air from moisture by passing it over or through substances having an aflinity for water, either before or after .it is refrigerated, and I do not claim, broadly, the use of any such substances, but only in the manner specified-that is, when the air is refrigerated and dehydrated simultaneously; but

What I do claim as new, and desire to secure by Letters Patent, is-

1. The process of simultaneously refrigerating and dehydrating air, which consists in exposing it to direct contact with cooled glycerine, as set forth.

2. The process of cooling air, which consists in passing the air in direct contact with such an incongealable liquid as is described, the latter being refrigerated by direct contact with surfaces cooled on their reverse side by any volatile refrigerant, as and for the purposes set forth.

3. The process of cooling air, which consists in bringing the air into direct contact with any such incongealable liquid as is described, said liquid being in spray, streams, or showers, and being refrigerated by contact with vessels containing a'volatile refrigerant, as and for the purposes set forth.

4. The combination of case L, tank B for containing incongealable liquid, having upper air-inlets I I and one or more bottom air-outlets, H, with refrigerating-coil O, as and for the purpose set forth.

5. The combination of case L, the tank B,

having side air-inlets I I and bottom air-outlet H, with refrigerant-coil0and fan F, as and for the purposes set forth.

6. The combination of case L, the tank B, having side air-inlets I I and bottom air-outlet H, with refrigerant-coil G, perforated tank A, and fan F, as and forthe purposes specified.

7. The combination of case L, tank B for incongealable liquid, having upper air-inlets I' I and one or more bottom air-outlets, H, with refrigerating-coil O and perforated tank A, as and for the purpose specified.

8. The combination of the case L, having controllable air inlet B and outlet 0, with tank B, coil 0, and fan F, as and for the purposes set forth.

In testimony that I claim the foregoing as my own invention I affix my signature in presence of two witnesses.

SAML. D. LOUNT.

Witnesses:

JOHN W. FRAZEE, 7 WM. MoNEIR. 

